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Low Beam Headlights Will Not Turn On

  1. Inspect fuses No. 14 (10-amp) and 15 (10-amp) located in junction block. See Figure. If either fuse is open, go to next step. If both fuses are okay, go to step  3.
  2. Remove low beam relay from junction block. Remove junction block fuses No. 14 and 15. Using DVOM, measure resistance between ground and low beam relay socket terminal No. 87. If resistance is less than 5 ohms, repair short to ground in low beam relay output circuit. Perform BODY VERIFICATION TEST  under VERIFICATION TESTS. If resistance is 5 ohms or greater, replace open fuse(s). Perform BODY VERIFICATION TEST  under VERIFICATION TESTS.
  3. Using scan tool, select BODY SENSORS. Read HEADLIGHT SW VOLTS. Rotate headlight switch through all positions. Compare with HEADLIGHT SWITCH VOLTAGE SPECIFICATIONS  table. If voltage is within specification, go to next step. If voltage is not within specification, replace left multifunction switch. See appropriate STEERING COLUMN SWITCHES article. Perform BODY VERIFICATION TEST  under VERIFICATION TESTS.
  4. Install a known-good relay in low beam relay socket. Operate low beam headlights. If low beam headlights do not operate correctly, go to next step. If low beam headlights operate correctly, replace defective relay. Perform BODY VERIFICATION TEST  under VERIFICATION TESTS.
  5. Remove low beam relay from junction block. Ensure fuses No. 14 and 15 are installed in junction block. Using DVOM, measure resistance between low beam relay socket terminal No. 87 and either right or left front head light connector. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or greater, replace junction block. Perform BODY VERIFICATION TEST  under VERIFICATION TESTS.
  6. Replace Body Control Module (BCM). See BODY CONTROL MODULE  under REMOVAL & INSTALLATION. Perform BODY VERIFICATION TEST  under VERIFICATION TESTS.
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